+/**
+ * Packet parsing for "private" payloads in the RTP specs.
+ *
+ * @param s stream context
+ * @param pkt packet in which to write the parsed data
+ * @param timestamp pointer in which to write the timestamp of this RTP packet
+ * @param buf pointer to raw RTP packet data
+ * @param len length of buf
+ * @param flags flags from the RTP packet header (PKT_FLAG_*)
+ */